#Requires -Modules @{ ModuleName = 'Pester'; ModuleVersion = '5.0.0' }

<#
    FR-029: the interactive editor can delete an existing rule.

    Remove-PersonaConfigRule is the pure function the [D] command calls after the
    operator confirms against the rule's id, name, and priority - the confirmation
    prompt itself lives in Edit-PersonaEngineConfig.ps1 and is covered by
    EditorStructuralEdits.Tests.ps1, which drives the real interactive loop.
#>

BeforeAll {
    $repoRoot = Split-Path (Split-Path $PSScriptRoot -Parent) -Parent
    . (Join-Path $repoRoot 'tests/TestHelpers.ps1')
    foreach ($file in (Get-PersonaSourceFile -RepoRoot $repoRoot)) { . $file }

    function New-TestRule {
        param([string] $Id, [int] $Priority)

        [pscustomobject]@{
            id          = $Id
            name        = "Rule $Id"
            description = 'A test rule.'
            enabled     = $true
            priority    = $Priority
            persona     = 'Employee'
            match       = [pscustomobject]@{
                operator   = 'all'
                conditions = @([pscustomobject]@{ type = 'property'; property = 'Department'; operator = 'isNotNull' })
            }
        }
    }
}

Describe 'Remove-PersonaConfigRule (FR-029)' {

    It 'removes the named rule' {
        $rules = @(
            (New-TestRule -Id 'RULE-0010-GUEST' -Priority 10),
            (New-TestRule -Id 'RULE-0900-EMPLOYEE' -Priority 900)
        )

        $result = Remove-PersonaConfigRule -Rules $rules -RuleId 'RULE-0010-GUEST'

        , $result | Should -BeOfType [array]
        $result.Count | Should -Be 1
        $result[0].id | Should -Be 'RULE-0900-EMPLOYEE'
    }

    It 'does not mutate the input collection' {
        $rules = @(
            (New-TestRule -Id 'RULE-0010-GUEST' -Priority 10),
            (New-TestRule -Id 'RULE-0900-EMPLOYEE' -Priority 900)
        )

        Remove-PersonaConfigRule -Rules $rules -RuleId 'RULE-0010-GUEST' | Out-Null

        $rules.Count | Should -Be 2
    }

    It 'throws when the id does not exist, rather than silently doing nothing' {
        $rules = @((New-TestRule -Id 'RULE-0010-GUEST' -Priority 10))

        { Remove-PersonaConfigRule -Rules $rules -RuleId 'RULE-9999-ABSENT' } | Should -Throw '*RULE-9999-ABSENT*'
    }

    It 'can remove the only remaining rule, leaving an empty collection' {
        $rules = @((New-TestRule -Id 'RULE-0010-GUEST' -Priority 10))

        $result = Remove-PersonaConfigRule -Rules $rules -RuleId 'RULE-0010-GUEST'

        , $result | Should -BeOfType [array]
        $result.Count | Should -Be 0
    }

    It 'a deletion that leaves zero enabled rules is caught by re-validation (PE-SEM-003)' {
        # Remove-PersonaConfigRule itself has no opinion on "zero enabled rules" - that
        # is VR-002's job. Exercised here to prove the editor's re-validation path
        # would in fact block this rather than silently accepting it.
        $document = New-TestConfigurationDocument
        ($document.rules | Where-Object { $_.id -eq 'RULE-0010-GUEST' }).enabled = $false
        $document.rules = Remove-PersonaConfigRule -Rules $document.rules -RuleId 'RULE-0900-EMPLOYEE'

        $path = Save-TestConfiguration -Document $document -Directory ([System.IO.Path]::GetTempPath())

        try {
            $result = Test-PersonaConfiguration -Path $path
            $result.IsValid | Should -BeFalse
            @($result.Findings | Where-Object Code -EQ 'PE-SEM-003').Count | Should -BeGreaterThan 0
        }
        finally {
            Remove-Item -LiteralPath $path -Force -ErrorAction SilentlyContinue
        }
    }
}